Magnetic traction apparatus.



D. L. LINDQUIST. MAGNETIC TRACTION APPARATUS.

APPLICATION FILED JUNE 27, 1907.

1,043,527. Patented Nov. 5, 1912.

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D. L. LINDQUIST.

MAGNETIC TRACTION APPARATUS. APPLICATION FILED JUNE 27, 1907. 17 043 521 Patented Nov. 5, 1912.

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UNITED STATES PATENT OFFICE.

DAVID L. LINDQU'IST, OF YONKERS, NEW YORK, ASSIGNOR T0 OTIS ELEVATOR COM- PANY, 0F JERSEY CITY, NEW JERSEYZ'A CORPORATION OF NEW JERSEY.

MAGNETIC TRACTION APPARATUS.

To (ZZZ whom it may concern."

Be it known that I, DAVID L. LINDQUIST, a subject of the King of Sweden, residing at Yonkers, in the county of Westchester and State of New York, have invented a new and useful Improvement in Magnetic Traction Apparatus, of which the following is a specification.

My invention relates to a magnetic traction apparatus, and is shown in the accompanying drawing as applied to a driving sheave in a traction elevator system.

The object of the invention is to provide a simple, practical and durable magnetic sheave which will effectually reduce slipping between the sheave and cable to a minimum by producing a magnetic pull betweenthe sheave and the cable.

Other objects of the invention will appear hereinafter, the novel combinations of elements being set forth in the appended claims.

In the accompanying drawings, Figure 1 is a view largely diagrammatic, showing'a traction elevator system with my invention applied thereto; Fig. 2 is an elevation, partly in section of the magnetic traction sheave with the slip rings removed; and Fig. 3 is a sectional view on the line ABCDE of Fig. 2, showing also the slip rings.

In Fig. 1 is shown an elevator car C, connected by ropes or cables 2 to a counterweight W, said ropes or cables passing over the sheaves 3 and 5, thence downwardly under the traction wheel T, and upwardly to and over the sheave 6. The arrangement of the sheaves and their number may be varied as desired and any type of car or counterweight suitably guided may be used.

The sheaves 3 and 5 are in this instance supported by the overhead beam 4, and the sheave 6 is mounted on the beam 7. The beams 4 and 7 may be in the same plane or the sheaves 5 and 6 may be supported on opposite sides of the beam 4.

A shunt wound motor M is here shown only for the sake of illustrating the invention, as any other source of power for driving the traction wheel or sheave T may be employed. The motor M is mounted on a bed-plate 8, as is also the standard 9 which Specification of Letters Patent.

Application filed June 27, 1907.

Patented Nov. 5, 1912.

Serial No. 381,020.

closed from the positive main by way of main line switch L to and through conductors 18,19 and 12, solenoid 20, conductor 21, contact strip 16, lever 11, conductors 22, 23 and 24, and main line switch L, to the negative main. Current through this circuit will excite the solenoid 20 and lift its coreto effect the closure of the switch B. This will close a circuit through the motor armature. It will be noted that the circuit wires leading from, the positive and negative mains to the reversing switches and from there to the motor armature are represented by heavy lines. The circuit through the motor armaturewhen the switch It is closed is as follows, .-from the positive main by wires 18, 19, to and through contacts 25, 26, wires 28, 33, armature brush 31, armature 32, brush 30, wire 34, contacts 35, 36, wires 37 23, 24 to the negative main. The shunt field is closed by means of the auxiliary switch X from the wire 18 and by way of contact 38, bridge piece 39, contact 40, wire 41, motor terminal 42, shunt field, motor terminal 43, wires 44, 24 to the negative main. If the lever 11 is moved in the oppositedirection, the solenoid 20 will be excited and the cir-, cuits to the motor reversed. When the armature circuit is closed, a shunt circuit is also closed from the point 45, by way of wire 46, terminal 47, winding 48 of the traction wheel'T, terminal 49, and wire 50 topoint 51.

The foregoing disclosure is for the pur pose of illustrating one application of my hub and a central opening or bore 56 for the armature shaft to which the wheel" is secured. The part 53' also has an annular extension 57 which closely fits over the extension 55', and the inner end of the extension 57 abuts against a shoulder on the part 52 when the parts are bolted together. The extension 57 spaces the disks 52, 53 apart so as to form an annular recess or space 59 for the magnet winding or coil 48. This space is enlarged by having the disks dished or hollowed out between the extension 57- and the outer peripheries of the disks. Between the extension 57 and the coil- 48 is a polygonal ring 58 as shown by dotted lines in Fig. 2 which may be made of wood or other suitable material for spacing thecoil from the extension 57 and holding it in a central position in the recess 59. Insulation 60 is interposed between the coil 48 and the disks 52, 53 and also between the coil and the ring 58. When the sheave is assembled the coil is clamped between the disks and held under compression so that the spaces-between the windings are completely filled and the coil held compactly and firmly in position to prevent relative rotation. The disks 52 and 53 are each provided with aseries of openings 61, 62, communicating with the recess 59 and providing for circulation of air about the coil 48.

The'peripheries of the disks 52 and 53 are provided with recesses 74 and 78, respectively. Between the disks and extending into these recesses is a ring or sleeve 63 of brass" or other suitable non-magnetic material. Surrounding this sleeve is a series of rings 64 of magnetic material, preferably wrought iron; The rings 64 are spaced apart and magnetically insulated from each other by a series ofbrassrings 65. The peripheries of the rings 64, 65 and the disks 52, 53 are provided with semi-circular or arc-shaped grooves or recesses 66, conforming to the shape of the cables which engage the sheave. The cables are made of iron or other magnetic material. It will thus be seen that a construction is provided in which the magnetic circuit around the coil 48 is normally open between the iron rings 64, but is-closed when the cables are in engagement with the sheave. That is, each cable when in position in one of the grooves 66 between two of the iron rings 64 completes the magnetic path from one ring to the other, and when there is a cable in each groove, a complete circuit for the magnetic lines of force around'the coil 48 is provided. When a current is passed through the coil 48 the cables in contact with the sheave willbe held firmly in place by a strong magnetic pull. This willgreatly reduce the tendency of slipping between the sheave and the cables.

The bolts 67 near the periphery of the sheave are composed of brass or other nonmagnetic metal, and coiiperate with the bolts 54 to hold the parts securely in position. These bolts 67 have their axes substantially in the circle of contact between the sleeve 61 and the rings 64, 65, and are thus in a position to exert their full clamping action on these rings. The sheave T is provided with flanges 68 which guide the cables and pre vent their running offthe side of the sheave.

Slip rings 69, 70 are secured to the sheave by bolts 71 tapped into the disk 52. The rings are electrically insulated from the bolts and from the magnetic frame by insulating bushings 72 on the bolts. These bushings are in engagement with flanges or projections 73 on the slip rings. One terminal. of the coil 48 is electrically connected to the slip ring 70 by the binding post 79, and a similar connection 77 is provided between the other terminal and the slip ring 69. Brushes 75, 76 l) are held in sliding engagement with the slip rings 70 and 69.

In operation, when the circuit through the motor is closed in the manner before explained, a current will be transmitted from the motor mains through the coil 48 of the magnetic sheave T. I This will create a strong magnetic field around the co1l, thc magnetic flux being through the iron rings 64 and the portion of the cables in contact with the sheave. As the cables are in contact with about half the circumference of the sheave, each cable will have a length equal to substantially half a circumference magnetized, and held against the sheave with a strong pull. The aortion of the cable leaving the sheave will be demagnetized as it moves away from the sheave, owing to the air gap introduced between the cable and sheave ofiering a large resistance to the lines of force. The magnetic flux is thus continually shifted to the lower part of the sheave where the cables are in contact while the sheave rotates. In this way the magnetic field is automatically kept in that portion of the sheave and cables where it is needed to accomplish its purpose.

I do not wish to be limited to the exact construction shown, as many modifications .in materials used and construction and arrangement of parts may he made within the scope of the invention as defined in the appended claims.

lVhat I claim is 2- 1. The combination with a sheave having grooves in its periphery, of a plurality of magnetically separate cables engaging the groovesand forming with the sheave a magnetic circuit, and means for producing a magnetic flux through the sheave and cables in a direction transverse to the grooves.

2. As an article of manufacture, a sheave or drum having its traction peripheral portion composed of alternate rings of magnetic and non-magnetic material.

3. As an article of manufacture, a'sheave having its peripheral portion composed of alternate rings of magnetic and non-magnetic material, the magnetic material extending outwardly beyond the non-magnetic material.

4t. As an article of manufacture, a sheave having its peripheralportion composed of magnetic and non-magnetic rings, the magnetic rings being of larger diameter than the non-magnetic rings.

5. In a magnetic sheave, the combination with two substantially disk-shaped members spaced apart at their peripheries, of a plu rality of alternate rings of magnetic and non-magnetic material in said space, and a magnetic coil between the disk-shaped members.

6. In a magnetic sheave, the combination with a coil, of magnetic material partially surrounding the coil and forming a partial magnetic circuit, a plurality of rings of magnetic material in the remainder of the circuit, and non-magnetic material interposed between the rings.

7. In a magnetic sheave, the combination with a coil, of magnetic material partially surrounding the coil, and alternate rings of magnetic and non-magnetic material completing the inclosure of'the coil.

8. In a magnetic sheave, the combination of two disks of magnetic material spaced apart, and a plurality of alternate rings of magnetic and non-magnetic material bridging the space between the disks.

9. In a magnetic sheave, the combination with two disks of magnetic material shaped to form an annular recess extending inwardly from the periphery, of a magnetic coil in the recess, and alternate rings of magnetic and non-magnetic material surrounding the coil and forming the peripheral surface of the sheave.

10. In a magnetic sheave, the combination with a coil, of magnetic material partially surrounding the coil, a plurality of alternate magnetic and non-magnetic rings bridging the remaining space, and non-magnetic ma terial interposed between the inner peripheries of the rings and the magnetic material.

11. In a magnetic sheave, the combination with a coil, of magnetic material forming a partial circuit around the coil, parallel rings of magnetic material in the remainder of the circuit, and nonmagnetic material between the adjacent rings, and between the inner peripheries of the rings and the magnetic material.

12. In a magnetic sheave, the combination with a coil, of magnetic material forming a partial circuit around the coil, and rings of magnetic material in the remainder of the circuit, saidrings being spaced apart from each other and also from the other magnetic material.

13. As an article of manufacture, a magnetic sheave having its peripheral portion composed of alternate rings of brass and iron.

14. As an article of manufacture, a magnetic sheave having its peripheral portion composed of spaced iron rings and insulat-. ing material.

15. In a magnetic sheave, the combination with a coil, of magnetic material partially surrounding the coil, a brass ring or sleeve bridging the remaining space, and a plurality of alternate iron and brass rings mounted on the brass sleeve.

16. In a magnetic sheave, the combination with two disks having annular telescoping projections forming a hub for the sheave and spacing the disks apart, of a coil surrounding the hub, insulating material interposed between the coil and hub, a ring or sleeve of non-magnetic material outside of the coil and bridging the space between the peripheral portions of the disks, a plurality of alternate magnetic and nonmagnetic rings mounted on the sleeve, and means for securing the parts together.

17 In a magnetic sheave, the combination with a disk of magnetic material having a central circular portion projecting from one side of the disk, of a second disk of magnetic material having an annular projection sur rounding the projection on the first disk and spacing the disks apart, a magnet coil in the annular space between the disks, insulating material interposed between the coil and the annular projection, a ring or sleeve of nonmagnetic material outside the coil and bridging the space between the disks, alternate rings of magnetic and non-magnetic material outside the sleeve and forming the peripheral portion of the sheave, said rings being shaped to form circumferential grooves in the sheave, each groove extending from one magnetic ring to the adjacent magnetic ring, bolts securing the parts together, slip rings secured to one of the disks, and electrical connections between the terminals of the coil and the slip rings.

18. In a magnetic sheave, the combination with a winding and a core and magnetic poles, of non-magnetic and magnetic mate rial alternately placed between said poles, and means for holding said material from relative movement.

19. In a magnetic sheave, the combination with a plurality of magnetic members, of a winding of insulated conductor associated with said members, a series of rings alternately non-magnetic and magnetic between the outer portions of said members, and

means for both securing said members together and preventing relativemovement of said rings.

20. The combination with a plurality of magnetic members and a winding associated therewith to form an electro-magnet, of a ring sleeve of non-magnetic material between the outer portions of said me1nbers,- a series of non-magnetic and magnetic rings between said outer portions and 011 said sleeve, and non-magnetic bolts to secure together said members and to also prevent movement of said rings relatively to each other or relatively to said members.

In testimony whereof, I have signed my 15 name to this specification in the presence of two subscribing witnesses.

DAVID L. LINDQUIST.

Witnesses: I

CHAS. M. NISSEN, NORMAN VEITOH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

